A realization that the field of anesthesiology was experiencing serious staffing shortages culminated in the early 1960s. To meet growing demands, in response to the shortage and with concerns over the increasing complexity of anesthesia and surgery, three anesthesiologists (Drs. Gravenstein, Steinhaus, and Volpitto) proposed the concept of an "anesthesia technologist" who would be a member of the anesthesia team and would be considered an "applied physiologist". This was the precursor to what is now the certified anesthesiologist assistant. The three doctors designed an educational program whereby matriculates would build on an undergraduate premedical education then obtain a master’s degree in anesthesiology. This person would perform the same job as the nurse anesthetist but would be able to go on to medical school if they desired. This new professional, the certified anesthesiologist assistant, or ACA, thus had the potential to alleviate the shortage that was occurring in anesthesia. The concept became reality in 1969 when the first CAA training program began accepting students at Emory University in Atlanta, Georgia, followed shortly thereafter by a second program at Case Western Reserve University in Cleveland, Ohio.
It was envisioned that this new anesthesia professional would have a bachelor's degree in science with premedical training and be awarded a master's degree that allowed for both vertical mobility toward a medical degree and lateral mobility into other areas requiring training in biomedical equipment and physiologic measurement. The certified anesthesiologist assistant would remain under the supervision of the anesthesiologist as "responsibility and immediate care of the patient must remain within the province of the anesthesiologist; consequently, personnel could not work independently but only under the immediate direction of the anesthesiologist. This provided an advantage for the anesthesiologist, as one physician could provide attention to several patients with the proper employment of the anesthesia team as described above.”
Since its inception, the certified anesthesiologist assistant profession has grown, though it remains a largely regionalized profession. This is due to the small number of educational programs, which until recently numbered only two, and to the limited number of jurisdictions, 17, where certified anesthesiologist assistants are authorized to practice. In 1989, the National Commission for Certification of Anesthesiologist Assistants was formed to establish a national certification process. Today, the American Society of Anesthesiologists considers certified anesthesiologist assistants to be mid-level anesthesia providers who work under the direction of an anesthesiologist and participate in the provision of anesthesia. Certified anesthesiologist assistants perform such tasks as administering drugs, obtaining vascular access, applying and interpreting monitors, establishing and maintaining patient airway, and assisting with preoperative assessment.
Since 2002, additional training programs have opened. Currently, states in which CAAs practice, either by state statute or by physician delegation, include Alabama, Colorado, Florida, Georgia, Kentucky, Michigan, Missouri, New Hampshire, New Mexico, Ohio, Oklahoma, South Carolina, Texas, Vermont, West Virginia, and Wisconsin. CAAs also practice in the District of Columbia and nationally at veterans hospitals under the Department of Veterans Affairs. Certified anesthesiologist assistants enjoy a dynamic profession that continues to realize exponential growth as evidenced by the addition of new training sites and new states opening to CAA practice.